Flags in public folders disappear when more than 25 flags are used

2 Jul 2014


      Hello,
I have been using flags in public folders for quite a while
with no problems. Once the flags were added to all clients
(Thunderbird), they were visible and synchronized properly.
Now I have added some new flags, and in the dovecot-keywords
files I see that I am now using more than 25 flags (in which
case they are not stored using an additional letter in the
filename). Now I see that newly added flags are only visible
in the client for a short time and then suddenly disappear.
How can I debug this, or what may be a reason for this?
Regards
Thomas Herrmann
root@mailsrv2:~# dovecot --version
2.1.7
root@mailsrv2:~#  dovecot -n
# 2.1.7: /etc/dovecot/dovecot.conf
# OS: Linux 3.2.0-4-amd64 x86_64 Debian 7.5 xfs
disable_plaintext_auth = no
log_timestamp = "%Y-%m-%d %H:%M:%S "
mail_fsync = never
mail_location = maildir:/home/vmail/adwin.de/%n/Maildir
mail_privileged_group = mail
managesieve_notify_capability = mailto
managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date ihave imapflags
namespace {
inbox = yes
location =
prefix =
separator = /
subscriptions = yes
type = private
}
namespace {
list = children
location = maildir:/home/vmail/public:INDEX=/home/vmail/adwin.de/%n/public
prefix = ADwin/
separator = /
subscriptions = no
type = public
}
passdb {
args = /etc/dovecot/dovecot-sql.conf
driver = sql
}
plugin {
acl = vfile
sieve = /home/vmail/adwin.de/%n/dovecot.sieve
sieve_dir = /home/vmail/adwin.de/%n/sieve
sieve_extensions = +imapflags +imap4flags
}
protocols = imap lmtp sieve
service auth {
unix_listener /var/spool/postfix/private/auth {
group = postfix
mode = 0660
user = postfix
}
unix_listener auth-master {
mode = 0600
user = vmail
}
user = root
}
service imap-login {
inet_listener imap {
address = *,::
port = 56143
}
inet_listener imaps {
address = *,::
port = 56993
ssl = yes
}
service_count = 0
}
service imap {
vsz_limit = 512 M
}
service lmtp {
unix_listener /var/spool/postfix/private/dovecot-lmtp {
group = postfix
mode = 0660
user = postfix
}
}
service managesieve-login {
executable = /usr/lib/dovecot/managesieve-login
service_count = 0
}
service managesieve {
executable = /usr/lib/dovecot/managesieve
}
ssl_ca =